Show HN: Mathpad – Physical keypad for typing math symbols

Show HN (score: 32)
Found: August 02, 2025
ID: 669

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Show HN: Mathpad – Physical keypad for typing math symbols Here's something different than your usual fare: A physical keypad that lets you directly type math!

Ever tried typing mathematical equations in your code IDE, email, or on Slack? You might know it can be tricky. Mathpad solves this with dedicated keys for Greek letters, calculus symbols, and more. Press the ∫ key and get ∫, in any application that accepts text. It uses Unicode composition, so it works everywhere: Browsers, chat apps, code editors, Word, you name it. Basically, anywhere you can type text, Mathpad lets you type mathematics.

I built Mathpad after getting frustrated with the friction of typing equations in e.g. Word, and what a pain in the ass it was to find the specific symbols I needed. I assumed that a product like Mathpad already existed, but that was not true and I had to build it myself.

It turned out to be pretty useful! Three years of solo development later, I'm launching on Crowd Supply. One of the trickiest parts of this project was finding someone who could manufacture custom keycaps with mathematical symbols. Shoutout to Loic at 3dkeycap.com for making it possible!

Fully open source (hardware + software): https://github.com/Summa-Cogni/Mathpad Campaign: https://www.crowdsupply.com/summa-cogni/mathpad Project log: https://hackaday.io/project/186205-mathpad-the-math-keypad

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